Highly Conductive and Robust Three-Dimensional Host with Excellent Alkali Metal Infiltration Boosts Ultrastable Lithium and Sodium Metal Anodes.

The direct utilization of metallic lithium and sodium as the anodes for rechargeable batteries would be highly advantageous, which has been considered as one of the most promising choices for next-generation high-energy-density storage devices. Although the induced safety concerns, inferior rate, and cycling performance severely hinder the commercialization of lithium metal batteries (LMBs) and sodium metal batteries (SMBs), the recent development of nanotechnology-based solutions really revives the lithium/sodium metal anodes for high-energy batteries. In this work, an ultrastable carbon textile (CT)-based host with excellent infiltration for both metallic Li and Na has been designed and exhibits more flat voltage profiles, lower stripping/plating overpotential, and better cycling stability both in symmetric cell and full cell configurations, even in additive-free carbonate-based electrolyte compared with pure Li/Na electrodes. The highly conductive and mechanically robust three-dimensional CTs not only offer a stable scaffold against hyperactive lithium and sodium but also enable uniform nucleation and growth during stripping/plating process, which effectively suppress the dendrite growth and stabilize the electrode dimension. This facile strategy provides new insights into the design of stable hosts with prestored alkali metal to address the multifaceted issues in LMBs and SMBs simultaneously.